1 files changed, 151 insertions, 0 deletions
diff --git a/plumbing/transport/ssh/common.go b/plumbing/transport/ssh/common.go
new file mode 100644
index 0000000..6f0f3d4
--- /dev/null
+++ b/plumbing/transport/ssh/common.go
@@ -0,0 +1,151 @@
+package ssh
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"strings"
+
+	"gopkg.in/src-d/go-git.v4/plumbing/transport"
+
+	"golang.org/x/crypto/ssh"
+)
+
+// New errors introduced by this package.
+var (
+	ErrAdvertistedReferencesAlreadyCalled = errors.New("cannot call AdvertisedReference twice")
+	ErrAlreadyConnected                   = errors.New("ssh session already created")
+	ErrAuthRequired                       = errors.New("cannot connect: auth required")
+	ErrNotConnected                       = errors.New("not connected")
+	ErrUploadPackAnswerFormat             = errors.New("git-upload-pack bad answer format")
+	ErrUnsupportedVCS                     = errors.New("only git is supported")
+	ErrUnsupportedRepo                    = errors.New("only github.com is supported")
+)
+
+type Client struct{}
+
+var DefaultClient = NewClient()
+
+func NewClient() transport.Client {
+	return &Client{}
+}
+
+func (c *Client) NewFetchPackSession(ep transport.Endpoint) (
+	transport.FetchPackSession, error) {
+
+	return newFetchPackSession(ep)
+}
+
+func (c *Client) NewSendPackSession(ep transport.Endpoint) (
+	transport.SendPackSession, error) {
+
+	return newSendPackSession(ep)
+}
+
+type session struct {
+	connected   bool
+	endpoint    transport.Endpoint
+	client      *ssh.Client
+	session     *ssh.Session
+	stdin       io.WriteCloser
+	stdout      io.Reader
+	sessionDone chan error
+	auth        AuthMethod
+}
+
+func (s *session) SetAuth(auth transport.AuthMethod) error {
+	a, ok := auth.(AuthMethod)
+	if !ok {
+		return transport.ErrInvalidAuthMethod
+	}
+
+	s.auth = a
+	return nil
+}
+
+// Close closes the SSH session.
+func (s *session) Close() error {
+	if !s.connected {
+		return nil
+	}
+
+	s.connected = false
+	return s.client.Close()
+}
+
+// ensureConnected connects to the SSH server, unless a AuthMethod was set with
+// SetAuth method, by default uses an auth method based on PublicKeysCallback,
+// it connects to a SSH agent, using the address stored in the SSH_AUTH_SOCK
+// environment var.
+func (s *session) connect() error {
+	if s.connected {
+		return ErrAlreadyConnected
+	}
+
+	if err := s.setAuthFromEndpoint(); err != nil {
+		return err
+	}
+
+	var err error
+	s.client, err = ssh.Dial("tcp", s.getHostWithPort(), s.auth.clientConfig())
+	if err != nil {
+		return err
+	}
+
+	if err := s.openSSHSession(); err != nil {
+		_ = s.client.Close()
+		return err
+	}
+
+	s.connected = true
+	return nil
+}
+
+func (s *session) getHostWithPort() string {
+	host := s.endpoint.Host
+	if strings.Index(s.endpoint.Host, ":") == -1 {
+		host += ":22"
+	}
+
+	return host
+}
+
+func (s *session) setAuthFromEndpoint() error {
+	var u string
+	if info := s.endpoint.User; info != nil {
+		u = info.Username()
+	}
+
+	var err error
+	s.auth, err = NewSSHAgentAuth(u)
+	return err
+}
+
+func (s *session) openSSHSession() error {
+	var err error
+	s.session, err = s.client.NewSession()
+	if err != nil {
+		return fmt.Errorf("cannot open SSH session: %s", err)
+	}
+
+	s.stdin, err = s.session.StdinPipe()
+	if err != nil {
+		return fmt.Errorf("cannot pipe remote stdin: %s", err)
+	}
+
+	s.stdout, err = s.session.StdoutPipe()
+	if err != nil {
+		return fmt.Errorf("cannot pipe remote stdout: %s", err)
+	}
+
+	return nil
+}
+
+func (s *session) runCommand(cmd string) chan error {
+	done := make(chan error)
+	go func() {
+		done <- s.session.Run(cmd)
+	}()
+
+	return done
+}